This invention relates to a magnetic recording medium. More particularly, it relates to a magnetic recording medium having long life and suited for application to magnetic discs, magnetic drums, magnetic tapes, magnetic cards and like devices.
Generally, magnetic recording media comprise a magnetic layer (a magnetic recording film) formed on various types of substrate made of organic or inorganic material. In use of such magnetic recording media for magnetic recording or reproduction, the surface of the magnetic layer is forced into a frictional contact with a magnetic recording head. The lowering of performance due to the wear of the magnetic layer caused by such frictional contact poses a serious problem for the magnetic recording media. For instance, in a magnetic disc device, when it is in normal operation, the magnetic head is in a state of being floated up under the floating force of an air film which is formed on the rotating disc surface. However, at the start or stoppage of rotation of the magnetic disc when no floating force is afforded or the floating force dies down, the magnetic head and the disc are brought into a contact sliding state. For reducing the wear of the magnetic recording medium in such contact sliding state to retain the floating characteristics of the magnetic head, it needs to provide a lubricant layer which firmly adheres to the magnetic recording film. It is known to provide a surface treatment layer on the magnetic recording film for improving the adhesion of the lubricant, as for instance disclosed in Japanese Patent Kokai (Laid-Open) No. 164430/82. This treatment consists in combining a fluorinated alkane such as tetrafluoroethylene teromer used as lubricant and a fluorine-containing surface treatment agent, but since such treatment can merely afford physical bond between the surface treatment agent and the magnetic layer, it proves unable to provide a satisfactorily strong bond between the surface treatment agent and the magnetic recording film, resulting in unsatisfactory wear resistance of the magnetic layer and unimproved durability of the magnetic recording medium.